/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.tool;

import org.apache.commons.cli.*;
import org.apache.iotdb.cli.utils.JlineUtils;
import org.apache.iotdb.exception.ArgsErrorException;
import org.apache.iotdb.isession.SessionDataSet;
import org.apache.iotdb.rpc.IoTDBConnectionException;
import org.apache.iotdb.rpc.RpcUtils;
import org.apache.iotdb.rpc.StatementExecutionException;
import org.apache.iotdb.session.Session;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.tsfile.read.common.RowRecord;
import org.apache.thrift.TException;
import org.jline.reader.LineReader;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.time.Instant;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.List;

/**
 * Export CSV file.
 *
 * @version 1.0.0 20170719
 */
public class ExportCsv extends AbstractCsvTool {

    private static final String TARGET_DIR_ARGS = "td";
    private static final String TARGET_DIR_NAME = "targetDirectory";

    private static final String TARGET_FILE_ARGS = "f";
    private static final String TARGET_FILE_NAME = "targetFile";

    private static final String SQL_FILE_ARGS = "s";
    private static final String SQL_FILE_NAME = "sqlfile";

    private static final String DATA_TYPE_ARGS = "datatype";
    private static final String DATA_TYPE_NAME = "datatype";

    private static final String QUERY_COMMAND_ARGS = "q";
    private static final String QUERY_COMMAND_NAME = "queryCommand";

    private static final String LINES_PER_FILE_ARGS = "linesPerFile";
    private static final String LINES_PER_FILE_ARGS_NAME = "Lines Per File";

    private static final String TSFILEDB_CLI_PREFIX = "ExportCsv";

    private static final String DUMP_FILE_NAME_DEFAULT = "dump";
    private static String targetFile = DUMP_FILE_NAME_DEFAULT;

    private static String targetDirectory;

    private static Boolean needDataTypePrinted;

    private static String queryCommand;

    private static String timestampPrecision;

    private static int linesPerFile = 10000;

    private static final int EXPORT_PER_LINE_COUNT = 10000;

    private static long timeout = -1;

    /**
     * main function of export csv tool.
     */
    public static void main(String[] args) {
        Options options = createOptions();
        HelpFormatter hf = new HelpFormatter();
        CommandLine commandLine = null;
        CommandLineParser parser = new DefaultParser();
        hf.setOptionComparator(null); // avoid reordering
        hf.setWidth(MAX_HELP_CONSOLE_WIDTH);

        if (args == null || args.length == 0) {
            System.out.println("Too few params input, please check the following hint.");
            hf.printHelp(TSFILEDB_CLI_PREFIX, options, true);
            System.exit(CODE_ERROR);
        }
        try {
            commandLine = parser.parse(options, args);
        } catch (ParseException e) {
            System.out.println(e.getMessage());
            hf.printHelp(TSFILEDB_CLI_PREFIX, options, true);
            System.exit(CODE_ERROR);
        }
        if (commandLine.hasOption(HELP_ARGS)) {
            hf.printHelp(TSFILEDB_CLI_PREFIX, options, true);
            System.exit(CODE_ERROR);
        }
        int exitCode = CODE_OK;
        try {
            parseBasicParams(commandLine);
            parseSpecialParams(commandLine);
            if (!checkTimeFormat()) {
                System.exit(CODE_ERROR);
            }

            session = new Session(host, Integer.parseInt(port), username, password);
            session.open(false);
            timestampPrecision = session.getTimestampPrecision();
            setTimeZone();

            if (queryCommand == null) {
                String sqlFile = commandLine.getOptionValue(SQL_FILE_ARGS);
                String sql;

                if (sqlFile == null) {
                    LineReader lineReader = JlineUtils.getLineReader(username, host, port);
                    sql = lineReader.readLine(TSFILEDB_CLI_PREFIX + "> please input query: ");
                    System.out.println(sql);
                    String[] values = sql.trim().split(";");
                    for (int i = 0; i < values.length; i++) {
                        dumpResult(values[i], i);
                    }
                } else {
                    dumpFromSqlFile(sqlFile);
                }
            } else {
                dumpResult(queryCommand, 0);
            }

        } catch (IOException e) {
            System.out.println("Failed to operate on file, because " + e.getMessage());
            exitCode = CODE_ERROR;
        } catch (ArgsErrorException e) {
            System.out.println("Invalid args: " + e.getMessage());
            exitCode = CODE_ERROR;
        } catch (IoTDBConnectionException | StatementExecutionException e) {
            System.out.println("Connect failed because " + e.getMessage());
            exitCode = CODE_ERROR;
        } catch (TException e) {
            System.out.println(
                    "Can not get the timestamp precision from server because " + e.getMessage());
            exitCode = CODE_ERROR;
        } finally {
            if (session != null) {
                try {
                    session.close();
                } catch (IoTDBConnectionException e) {
                    exitCode = CODE_ERROR;
                    System.out.println(
                            "Encounter an error when closing session, error is: " + e.getMessage());
                }
            }
        }
        System.exit(exitCode);
    }

    private static void parseSpecialParams(CommandLine commandLine) throws ArgsErrorException {
        targetDirectory = checkRequiredArg(TARGET_DIR_ARGS, TARGET_DIR_NAME, commandLine);
        targetFile = commandLine.getOptionValue(TARGET_FILE_ARGS);
        needDataTypePrinted = Boolean.valueOf(commandLine.getOptionValue(DATA_TYPE_ARGS));
        queryCommand = commandLine.getOptionValue(QUERY_COMMAND_ARGS);
        String timeoutString = commandLine.getOptionValue(TIMEOUT_ARGS);
        if (timeoutString != null) {
            timeout = Long.parseLong(timeoutString);
        }
        if (needDataTypePrinted == null) {
            needDataTypePrinted = true;
        }
        if (targetFile == null) {
            targetFile = DUMP_FILE_NAME_DEFAULT;
        }
        timeFormat = commandLine.getOptionValue(TIME_FORMAT_ARGS);
        if (timeFormat == null) {
            timeFormat = "default";
        }
        timeZoneID = commandLine.getOptionValue(TIME_ZONE_ARGS);
        if (!targetDirectory.endsWith("/") && !targetDirectory.endsWith("\\")) {
            targetDirectory += File.separator;
        }
        if (commandLine.getOptionValue(LINES_PER_FILE_ARGS) != null) {
            linesPerFile = Integer.parseInt(commandLine.getOptionValue(LINES_PER_FILE_ARGS));
        }
    }

    /**
     * commandline option create.
     *
     * @return object Options
     */
    private static Options createOptions() {
        Options options = createNewOptions();

        Option opTargetFile =
                Option.builder(TARGET_DIR_ARGS)
                        .required()
                        .argName(TARGET_DIR_NAME)
                        .hasArg()
                        .desc("Target File Directory (required)")
                        .build();
        options.addOption(opTargetFile);

        Option targetFileName =
                Option.builder(TARGET_FILE_ARGS)
                        .argName(TARGET_FILE_NAME)
                        .hasArg()
                        .desc("Export file name (optional)")
                        .build();
        options.addOption(targetFileName);

        Option opSqlFile =
                Option.builder(SQL_FILE_ARGS)
                        .argName(SQL_FILE_NAME)
                        .hasArg()
                        .desc("SQL File Path (optional)")
                        .build();
        options.addOption(opSqlFile);

        Option opTimeFormat =
                Option.builder(TIME_FORMAT_ARGS)
                        .argName(TIME_FORMAT_NAME)
                        .hasArg()
                        .desc(
                                "Output time Format in csv file. "
                                        + "You can choose 1) timestamp, number, long 2) ISO8601, default 3) "
                                        + "user-defined pattern like yyyy-MM-dd\\ HH:mm:ss, default ISO8601 (optional)")
                        .build();
        options.addOption(opTimeFormat);

        Option opTimeZone =
                Option.builder(TIME_ZONE_ARGS)
                        .argName(TIME_ZONE_NAME)
                        .hasArg()
                        .desc("Time Zone eg. +08:00 or -01:00 (optional)")
                        .build();
        options.addOption(opTimeZone);

        Option opDataType =
                Option.builder(DATA_TYPE_ARGS)
                        .argName(DATA_TYPE_NAME)
                        .hasArg()
                        .desc(
                                "Will the data type of timeseries be printed in the head line of the CSV file?"
                                        + '\n'
                                        + "You can choose true) or false) . (optional)")
                        .build();
        options.addOption(opDataType);

        Option opQuery =
                Option.builder(QUERY_COMMAND_ARGS)
                        .argName(QUERY_COMMAND_NAME)
                        .hasArg()
                        .desc("The query command that you want to execute. (optional)")
                        .build();
        options.addOption(opQuery);

        Option opLinesPerFile =
                Option.builder(LINES_PER_FILE_ARGS)
                        .argName(LINES_PER_FILE_ARGS_NAME)
                        .hasArg()
                        .desc("Lines per dump file.")
                        .build();
        options.addOption(opLinesPerFile);

        Option opHelp =
                Option.builder(HELP_ARGS)
                        .longOpt(HELP_ARGS)
                        .hasArg(false)
                        .desc("Display help information")
                        .build();
        options.addOption(opHelp);

        Option opTimeout =
                Option.builder(TIMEOUT_ARGS)
                        .longOpt(TIMEOUT_NAME)
                        .hasArg()
                        .desc("Timeout for session query")
                        .build();
        options.addOption(opTimeout);
        return options;
    }

    /**
     * This method will be called, if the query commands are written in a sql file.
     *
     * @param filePath
     * @throws IOException
     */
    private static void dumpFromSqlFile(String filePath) throws IOException {
        try (BufferedReader reader = new BufferedReader(new FileReader(filePath))) {
            String sql;
            int index = 0;
            while ((sql = reader.readLine()) != null) {
                dumpResult(sql, index);
                index++;
            }
        }
    }

    /**
     * Dump files from database to CSV file.
     *
     * @param sql   export the result of executing the sql
     * @param index used to create dump file name
     */
    private static void dumpResult(String sql, int index) {
        final String path = targetDirectory + targetFile + index;
        try {
            SessionDataSet sessionDataSet = session.executeQueryStatement(sql, timeout);
            List<Object> headers = new ArrayList<>();
            List<String> names = sessionDataSet.getColumnNames();
            List<String> types = sessionDataSet.getColumnTypes();
            if (needDataTypePrinted) {
                for (int i = 0; i < names.size(); i++) {
                    if (!"Time".equals(names.get(i)) && !"Device".equals(names.get(i))) {
                        headers.add(String.format("%s(%s)", names.get(i), types.get(i)));
                    } else {
                        headers.add(names.get(i));
                    }
                }
            } else {
                headers.addAll(names);
            }
            writeCsvFile(sessionDataSet, path, headers, linesPerFile);
            sessionDataSet.closeOperationHandle();
            System.out.println("Export completely!");
        } catch (StatementExecutionException | IoTDBConnectionException | IOException e) {
            System.out.println("Cannot dump result because: " + e.getMessage());
        }
    }

    public static String timeTrans(Long time) {
        switch (timeFormat) {
            case "default":
                return RpcUtils.parseLongToDateWithPrecision(
                        DateTimeFormatter.ISO_OFFSET_DATE_TIME, time, zoneId, timestampPrecision);
            case "timestamp":
            case "long":
            case "number":
                return String.valueOf(time);
            default:
                return ZonedDateTime.ofInstant(Instant.ofEpochMilli(time), zoneId)
                        .format(DateTimeFormatter.ofPattern(timeFormat));
        }
    }

    public static void writeCsvFile(
            SessionDataSet sessionDataSet, String filePath, List<Object> headers, int linesPerFile)
            throws IOException, IoTDBConnectionException, StatementExecutionException {
        int fileIndex = 0;
        boolean hasNext = true;
        while (hasNext) {
            int i = 0;
            final String finalFilePath = filePath + "_" + fileIndex + ".csv";
            final CSVPrinterWrapper csvPrinterWrapper = new CSVPrinterWrapper(finalFilePath);
            csvPrinterWrapper.printRecord(headers);
            while (i++ < linesPerFile) {
                if (sessionDataSet.hasNext()) {
                    RowRecord rowRecord = sessionDataSet.next();
                    if (rowRecord.getTimestamp() != 0) {
                        csvPrinterWrapper.print(timeTrans(rowRecord.getTimestamp()));
                    }
                    rowRecord
                            .getFields()
                            .forEach(
                                    field -> {
                                        String fieldStringValue = field.getStringValue();
                                        if (!"null".equals(field.getStringValue())) {
                                            if (field.getDataType() == TSDataType.TEXT
                                                    && !fieldStringValue.startsWith("root.")) {
                                                fieldStringValue = "\"" + fieldStringValue + "\"";
                                            }
                                            csvPrinterWrapper.print(fieldStringValue);
                                        } else {
                                            csvPrinterWrapper.print("");
                                        }
                                    });
                    csvPrinterWrapper.println();
                } else {
                    hasNext = false;
                    break;
                }
            }
            fileIndex++;
            csvPrinterWrapper.flush();
            csvPrinterWrapper.close();
        }
    }
}
